It is widely assumed that when an individual receives a choice between two alternatives, he or she assigns a value to them on a common scale. The probability of choosing one of the alternatives depends upon the difference between these values. Although this general conceptualization (called utility theory) is pervasive, and carries great intuitive appeal, its major implications have been tested infrequently. For example, one type of utility theory implies that if A is chosen over B at least 50% of the time, and B is chosen over C at least 50% of the time, A will be chosen over C at least 50% of the time. A stronger type of utility theory makes a more precise prediction: If an individual is indifferent between two alternatives, she or he will choose them over a third alternative exactly the same percentage of the time. Both of these relationships are forms of transitivity, and to the extent that choices are transitive, our ability to predict choices would be greatly enhanced. The present research tests these two forms of transitivity using two kinds of alternatives: foods, and schedules of reinforcement, or work requirements. Another implication of utility theories is that choice depends solely upon the value of the alternatives. However, it is known that choice may be conditional upon other factors such as the alternative that the subject has chosen last. The present research examines the conditions under which such conditional probabilities are most likely to appear, and in so doing, it will help to specify the limitations of utility theories. Finally, if choice depends only upon the value of alternatives, the circumstances under which a person makes choices should be irrelevant. The proposed research tests this inplication by varying aspects of the choice situation while holding constant the alternatives between which the person chooses.